In prior art load control systems, standard mechanical toggle switches are often replaced by more advanced load control devices (such as dimmer switches) that control the amount of power delivered from an AC power source to an electrical load. This procedure requires that the old mechanical toggle switch be un-wired and removed from the load control system and the new load control device to be connected to the electrical wiring. Typically, such a procedure must be performed by an electrical contractor or other skilled installer. The average consumer may not feel comfortable to complete the installation of the load control device. Accordingly, there is a need for a load control system that may be installed in an existing installation having a mechanical toggle switch without requiring any electrical work.